1. Field of the Disclosure
The disclosure relates to Voice over Internet Protocol (VoIP) telephone communications.
2. Introduction
In a digital telephonic communication system, VoIP packets are usually sent using a “fire and forget” protocol such as User Datagram Protocol (UDP) or User Datagram Protocol/Realtime Transport Protocol (UDP/RTP). UDP has no retransmission (nor any other error control mechanism) to fix errors or replace lost packets. In fact, UDP packet delivery is not guaranteed, and packets may be dropped when a network becomes congested. Thus, the main cause of voice quality degradation in VoIP systems arises from lost and late (or misordered) packets. If these packets are fed to an unprotected voice decoder, it is possible that gaps, additional delay, and garbled speech can result.